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 Table of Contents  
Year : 2023  |  Volume : 13  |  Issue : 1  |  Page : 30-35

Subjective assessment of bonded fixed lingual retainers: A questionnaire survey

Department of Orthodontics and Dentofacial Orthopaedics, K M Shah Dental College and Hospital, Sumandeep Vidyapeeth University, Vadodara, Gujarat, India

Date of Submission18-Aug-2021
Date of Acceptance30-Apr-2022
Date of Web Publication06-Dec-2022

Correspondence Address:
Dr. Vinaykumar D Shah
No. 4, Department of Orthodontics and Dentofacial Orthopaedics, K.M.Shah Dental College and Hospital, Nr Dhiraj General Hospital, Sumandeep Vidyapeeth University, Pipariya, Vadodara - 391 760, Gujarat
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/aihb.aihb_122_21

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Aims: This study aimed to assess the patients' subjective assessment of bonded fixed lingual retainers after completion of active orthodontic treatment. Objective: A questionnaire comprising 11 questions evaluated the patients' experience with bonded fixed lingual retainer. Materials and Methods: The content was validated by a group of seven experienced orthodontists. The questionnaire survey was run using Google Forms, responded by 45 (50.6%) males and 44 (49.4%) females between the ages ranging from 19 to 42 years. Their responses were rated on a Visual Analogue Scale as applicable. Cronbach's alpha test was utilised for assessing the reliability, and the Chi-square test was used for the quantitative variables. Results: 33.7% of individuals were most comfortable, and 2.2% had severe discomfort during retainer placement. 6.6% of individuals had severe difficulty maintaining oral hygiene in the upper arch and 4.4% in lower teeth and gums, respectively. 2.2% had severe difficulty in speech. 85.4% had no tongue ulceration. 37.1% of respondents had a very good overall experience with fixed bonded lingual retainer, 59.5% had mild problems and only 1.1% had severe problems with a very bad experience. Conclusions: The study concluded that the overall experience of respondents with fixed lingual bonded retainer had mild problems. It was comfortable for most of the patients in maintaining oral hygiene with mild difficulty in speech and chewing. The cause of failure of the retainer was mainly due to bond failure or broken wire in the retainer.

Keywords: Bonded lingual retainer, patients' subjective assessment, questionnaire study

How to cite this article:
Kulkarni NB, Shah VD. Subjective assessment of bonded fixed lingual retainers: A questionnaire survey. Adv Hum Biol 2023;13:30-5

How to cite this URL:
Kulkarni NB, Shah VD. Subjective assessment of bonded fixed lingual retainers: A questionnaire survey. Adv Hum Biol [serial online] 2023 [cited 2023 Mar 27];13:30-5. Available from: https://www.aihbonline.com/text.asp?2023/13/1/30/362698

  Introduction Top

Treatment success in orthodontics is determined by facial aesthetics, occlusion and stability.[1] Retaining the results of orthodontically corrected malocclusions has been discussed in the literature since the beginning of the 20th century.[2],[3] Orthodontic retention is defined as the phase of treatment, which attempts to maintain teeth in their corrected positions after active orthodontic treatment.[4] Angle proposed that the problems encountered during the retention period could be greater in comparison to orthodontic treatment.

This period can be divided into retention and post-retention phases. During the retention phase, the reorganisation of the periodontal ligament occurs over the first 3 to 4 months. The gingival collagen network typically takes 4 to 6 months to remodel, and the elastic supracrestal fibres can remain deviated for up to 232 days.[5]

The retention phase is considered to be a continuation of orthodontic treatment.[6] The post-retention phase, which begins after the retention phase has ended, lasts the rest of the patients' life. During this period, teeth are subjected to neuromuscular forces, dentoalveolar development and growth.[7]

The literature shows that there are variations in the retention protocols used following active orthodontic treatment.[8],[9],[10] To improve post-treatment stability, Blake and Bibby[11] suggested six treatment principles: (1) the patients' pre-treatment lower arch form should be maintained; (2) lower inter-canine width should be maintained; (3) account for mandibular arch length decrease;(4) the most stable lower incisor position is the pre-treatment position; (5) fiberotomy is an effective means of reducing rotational relapse and (6) lower incisor approximation aids in preventing relapse.

The retainers can be either fixed or removable. Fixed retainers are usually bonded or fixed to the palatal or lingual surfaces of the teeth. The removable retainers can be removed at the patients' will and are good for the maintenance of oral hygiene. There is no exact duration of time for which retainers are to be worn, but studies show that for patients who wore retainers for 2 years or lesser, the risk of long-term relapse of teeth was comparatively more.[12]

The bonded fixed lingual retainer is effective in maintaining the alignment after active orthodontic treatment in a very high percentage of patients.[13] There have also been few published studies regarding retainer compliance with Hawley retainers versus vacuum-formed retainers (VFRs). Hichens et al.[14] in 2007 surveyed patient satisfaction with Hawley retainers and VFRs at 3 and 6-month post-treatment intervals and found equal satisfaction with both.

Subjective research analyses human perspectives and records their experiences. It is phenomenological research that relates the experiences of an individual and highlights the importance of individual personal perspective and their interpretation.[15] Subjective assessment can be unstructured, semi-structured or structured. Hence, an attempt was made to discern the patients' subjective assessment during the post-retention phase with a bonded fixed lingual retainer.[16],[17]

  Materials and Methods Top

This questionnaire study was started after obtaining ethical approval from the university institutional ethical committee (ETH/2021/023). The sample size for the study was determined by using 'G power software'. A total sample size of 80 participants considering a dropout of 20% was determined by keeping the effect size fixed at 0.50, with an alpha error of 0.05 and a power of 0.95. Participants included in the study were seven experts specialised in orthodontics. Patients of any age group who had maxillary or mandibular or combination of both fixed lingual retainer as their retention plan of treatment and who can read, write and understand English were included in the study. They should also have a valid E-mail id. Participants who were not willing to be a participant in the study, patients with any developmental anomalies or syndromic condition and patients wearing other types of retainer other than fixed lingual retainer were excluded from the study. The necessary details of the participants were obtained from the archives of the department.

A questionnaire that assessed the perception of retainers in terms of time, comfort, appearance, maintaining oral hygiene, retainer breakage, tongue ulceration, chewing efficiency and speech was formulated by the primary investigator, and it was subjected to content validity. The formulated questionnaire was given to a group of seven orthodontists. Each reviewer independently rated the relevance of each question using a 4-point Likert scale (1 = not relevant, 2 = somewhat relevant, 3 = relevant and 4 = very relevant). The content validity index developed by Schneider E (1986)[18] was used to estimate the validity of the items. A rating of three or four indicates the content is valid and consistent. Further, suggestion for improvement was accepted, with the final questionnaire modified based on content validity.

Before the final questionnaire survey was initiated, changes were made as required to enable a better understanding of the questions by the respondents, and the arrangement of the questions was ensured for its efficiency. The construct validity was determined using exploratory factor analysis for 11 questions on a Visual Analogue Scale (VAS) rating scale, based solely on the ability to perform activities of daily living (ADLs).[18] Where score 0 is more comfortable, 1 to 3 is mild discomfort, 4 to 6 is moderate discomfort and 7 to 10 is severe discomfort. Finally, 11 questions survey instrument was developed [Table 1].
Table 1: Questionnaire

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A Google Forms with a link was generated and circulated among all the participants included in the study through E-mail and WhatsApp. The cover page of the questionnaire included a short introduction regarding the objectives, procedures, the voluntary nature of participation, declarations of confidentiality and anonymity. The questionnaire was answered by 89 respondents from 23 December 2020 to 10 January 2021. The responses of the questionnaire were accepted until 20 days from 23 December 2020 to 10 January 2021. A maximum of three times the reminder mail and WhatsApp was sent to all the respondents with an interval of 5 days. The responses given by the respondents were recorded. Respondents could submit their answers only when all the questions were finished. The questionnaire could be accessed through an E-mail account, and only a one-time response was permitted. Six questions were assessed on VAS, two questions were close ended (Yes/No) and three questions were open ended. All statistical analyses were performed using the IBM SPSS Statistics 21 Vadodara Gujarat India. Statistics 21®. The Cronbach's alpha test was utilised for assessing the reliability of the questions incorporated in the study, and the Chi-square test was used for the quantitative variables to determine the significance and relationship between responses to each question.

  Results Top

Content validity of all the 11 questions revealed a score of 4 and 3 for indicating that the content was valid and consistent. The Cronbach's alpha coefficient for 11 questions was 0.853, which suggested relatively high internal validity and consistency [Table 2]. A total of 89 respondents, 45 (50.6%) males and 44 (49.4%) females between 19 and 42 years, with a mean age of 27.96 (SD, 4.68), were included in the study [Table 3].
Table 2: Cronbach's alpha test

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Table 3: Sample demographics

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When the placement site of the fixed bonded lingual retainers was appraised among the respondents included in the study, a total of 68 (76.8%) respondents had fixed permanent bonded lingual retainer in both arches, 19 (21.3%) had only in the lower arch and 2 (2.2%) had only in the upper arch (Question No. 1) [Figure 1].
Figure 1: Site of placemen

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When the duration of placement of retainers was appraised, it was observed that a total of 2 (2.2%) respondents had 1 month or less, 16 (18%) respondents had between 1 and 3 months, 34 (38.2%) respondents had for 3–6 months, 17 (19.1%) respondents were between 6 and 12 months and 20 (22.5%) respondents had more than 12 months of duration from the time the lingual retainer was placed in their mouth (Question No. 2) [Figure 2].
Figure 2: Time of retainer placed

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When the comfort level was appraised at the time of placement, a total of 30 (33.7%) respondents had selected score 0, 52 (58.4%) selected score range 1–3, 5 (5.6%) selected score range between 4 and 6 and 2 (2.2%) selected score range 7–10 (Question No. 3)

The ease of oral hygiene maintenance of upper arch was recorded using VAS score, a total of 26 (29.2%) had selected score 0, 55 (61.9%) selected score range 1–3, 2 (2.2%) selected score range between 4 and 6 and 6 (6.6%) selected score range 7–10. In the lower arch ease of oral hygiene maintenance, a total of 27 (30.3%) had selected score 0, 55 (61.8%) selected score range 1–3, 3 (3.3%) selected score range between 4 and 6 and 4 (4.4%) selected score range 7–10 (Question No. 4, 5)

The difficulty of speech with the retainer was recorded. A total of 39 (43.8%) respondents had selected score 0, 42 (47.2%) selected score range 1–3, 6 (6.7%) selected score range between 4 and 6 and 2 (2.2%) selected score range 7–10 (Question No. 6).

The presence of any signs of tongue ulcerations was also enquired; a total of 76 (85.4%) respondents had selected No and the rest 13 (14.6%) selected Yes (Question No. 7). The level of hindrance while chewing with the fixed lingual retainer was recorded; a total of 34 (38.2%) had selected score 0, 48 (53.9%) selected score range 1–3, 6 (6.7%) selected score range between 4 and 6 and 1 (1.1%) selected score range 7–1 orthodontically 0 (Question No. 8).

Respondents were asked whether they had to get their lingual retainers replaced; a total of 63 (70.78%) had selected No and 26 (29.2%) selected Yes. However, a total of 14 (15.7%) respondents got their retainer replaced due to deboning from the teeth, seven respondents replaced their retainer due to wire fracture and 5 replaced their retainer due to drifting of front teeth (Question No. 9,10).

When the overall experience of the bonded lingual retainer was analysed, a total of 33 respondents (37.1%) had selected score 0, 50 (56.1%) selected score range 1–3, 5 (5.6%) selected score range between 4 and 6 and 1 (1.1%) selected score range 7–10 (Question No. 11).

  Discussion Top

Orthodontists strive to balance occlusion facial aesthetics and ultimately maintain the results achieved after treatment. Attaining the goal of good stability is dependent not only on the practitioner's skills but also on the knowledge of the patients' willingness and preferences to comply with the prescribed protocols of retention. To analyse the patient perspective and their experiences, a structured subjective assessment that comprised a questionnaire on fixed bonded lingual retainers was utilised.

The advantages of better response rate, reduced outlay, real-time access, convenience, design flexibility and no requirement of an additional person to interpret the information provided by the respondent inclined us to select the online platform to conduct the study.

Hoax survey, respondent availability and cooperation problems were considered to be the limitations of the online study which were minimised by allowing the respondent to participate in the study only once and sending reminders. Online questionnaire surveys allow larger samples to be surveyed in similar periods.[19],[20]

Little[8],[9] found that long-term alignment is both variable and unpredictable. It has been reported that 40% to 90% of patients had unacceptable dental alignment 10 years post-orthodontic treatment.[6],[21] Alterations in arch form, growth, neuromuscular influence, rebound in the collagen or elastic supracrestal fibres, a compensatory eruption of the dentition, the natural mesial drift of the dentition and inadequate periods of retention have been described as the potential causes of malalignment of orthodontically treated dentitions. Melrose and Millett,[21]in their review of evidence relating to orthodontic retention and relapse, stated that stability could be achieved if forces from the periodontal and gingival tissues, orofacial soft tissues, occlusion and post-treatment facial growth achieve a form of equilibrium. Some orthodontists state that long-term retention is the only way to prevent relapse.[22]

This questionnaire survey addressed patients' satisfaction with the treatment rendered stability and relapse of treatment, patient compliance with retention protocols and patient satisfaction with the prescribed retainers concerning the appearance, speech, ease of maintaining oral hygiene, ease of maintaining the retainer and need for replacement retainers.

Retainers used in orthodontic retention may be fixed to the dentition, such as a bonded wire, or removable, such as a Hawley or Essix appliance. A fixed retainer is fabricated using either a flexible multi-stranded, rigid titanium or a stainless-steel wire bonded to either all or only some (i.e., cuspids) of the lower anterior teeth. A significant advantage of this form of retention is the lack of need for active patient compliance. Disadvantages have been reported to include potential gingival inflammation and the patients' belief that the orthodontist is responsible for breakage.

Schneider and Ruf suggested that when occlusions are corrected to ideal parameters, the achieved dental overjet, overbite and masticatory forces are directly transmitted to the upper fixed retainer, leading to frequent failure. Still in the extraction cases, there are maximum chances of relapse due to the use of other forms of retention and are dependent on patient compliance. Hence, these issues are best avoided by the use of fixed lingual permanent retainer in the generalised spacing, midline diastema, extraction and severe crowding cases.[23]

In the mandibular arch, the type of retainer preference by the orthodontist was bonded retainer, followed by the Essix and then the Hawley retainer. Renkema et al. Investigated the effectiveness of mandibular canine to canine-bonded retainers and concluded that they are effective in maintaining the alignment of the mandibular anterior region after completion of active orthodontic treatment.[24]

Pratt et al. Stated in both the maxillary and mandibular arch, bonded retainers were rated the most aesthetic, followed by Essix retainers. However, the patient compliance with the removable retainer is not excellent because of irregular wear and misplacement. Hence, bonded retention should be evaluated as a preferred protocol over the removable retainers.

There were a total of 89 respondents, the majority of the respondents had both maxillary and mandibular bonded lingual retainers in their mouth (76.8%), followed by 21.3% in the mandibular arch and only 2.2% had in the maxillary arch.[25]

The comfort level at the time of placement of fixed lingual bonded retainer (33.7%) was most comfortable, 58.4% had mild discomfort, 5.6% had moderate discomfort and 2.2% had severe discomfort.

Respondent found oral hygiene maintenance to be easy for both maxillary and mandibular arches, 29.2% and 30.3%, respectively, followed by 61.9% and 61.8% had found mild difficulty. However, a total of 8.8% and 7.7% of respondents found it moderate to great difficulty in the upper and lower arch, respectively.

The oral hygiene maintenance in the post-retention phase is evaluated by the presence of plaque and calculus. Literature suggests that a minimum of 4–12 h is required for plaque formation followed by hardening, which takes place in 48–72 h, and calcification starts by 10–12 days.[26],[27] The process of calcification varies among individuals depending on their salivary pH and the amount of calcium and other substances.[28] A further study can be planned on the effect of retainer configuration on salivary pH and calcium. The majority of respondents were able to sense the oral hygiene issues in a span of 3–6 months of experience after placement of retainers.

In the literature, it has been noted that bonded retainers can complicate oral hygiene procedures and accumulate plaque and calculus.[22] Some studies report that multi-stranded wires tend to accumulate more plaque than stainless steel round wires,[23] while others report no difference in plaque accumulation based on the type of wire used as a bonded retainer.

A higher percentage of respondents had mild difficulty with speech, i.e., 47.2%, were as 43.8% respondents did not experience any difficulty in speech. A total of 8.9% of respondents had moderate-to-severe difficulty during speech. Hichens et al. Published that Hawley retainers cause greater discomfort as compared to Essix retainers due to their interference with speech. Concerning the maxillary arch, Hawley retainers affected speech most often (81%), followed by Essix (62%) and then bonded retainers (8%).

An utmost number of respondents, i.e., 85.4%, did not experience any tongue ulceration due to a fixed lingual retainer. Only 14.6% of respondents had noticed ulceration on the tongue. 38.2% of respondents felt no interference of bonded lingual retainers in chewing, while a majority of respondents, i.e., 53.9%, found mild difficulty. However, a total of 7.8% found moderate-to-severe difficulty.

The majority of respondent's, 70.78%, did not replace their fixed lingual retainer. However, only 29.2% of respondents had replaced their retainer in that 15.7% replaced retainer was due to bond failure of retainer from their teeth. Around 7.8% got replaced retainer as the wire got fractured, and 5.6% had a loss of alignment while having retainer in the mouth.

Usually, copper, nickel, titanium or a combination, Elgiloy, triple-stranded, five-stranded, coaxial wires and twisted ligature wires are utilised for the fabrication of retainer. Based on the archives, the respondents included in the study had twisted ligature wire in the retainer. This observation suggests that the dead soft ligature wire is more prone to fracture and loss of alignment.

Zachrisson reported the clinical failure rate of directly bonded retainers to be low, at 5%. In another study, Artun and Marstrander[24] reported the failure rate of a well-contoured bonded retainer placed close to the alveolar ridge as 10%. Kartal Y et al. and Schneider and Ruf reported a high rate of failure of bonded retainers (up to 35%). Hence, the selection of wire and adhesive plays a significant role in the successful management of the retention protocol.

37.1% of respondents had a very good overall experience with fixed bonded lingual retainer,[29] 56.1% had found very mild problems but had a good experience, only 5.6% had found moderate problems and 1.1% had found severe problems and had a very bad experience.

  Conclusion Top

The analysis of this study would help the clinician to accredit the experience of all the respondents and imply it on retention management. The observations of this study revealed a positive patients experience with the usage of fixed bonded lingual retainer. A higher number of patients had bonded lingual retainer in maxillary and mandibular arches. A significant advantage of this form of retention is the lack of need for active patient compliance. A mild problem in the overall experience was observed with the bonded lingual retainer. The majority of the patients had mild difficulty in speech and chewing. The cause of failure of the retainer was mainly due to bond failure or fractured wire. The majority of the respondents had mild oral hygiene issues.

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  References Top

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Little RM, Riedel RA, Artun J. An evaluation of changes in mandibular anterior alignment from 10 to 20 years post retention. Am J Orthod Dentofacial Orthop. 1988;93:423-8.  Back to cited text no. 3
Little RM. Stability and relapse of dental arch alignment. Br J Orthod. 1990;17:235-41.  Back to cited text no. 4
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White DJ. Dental calculus: recent insights into occurrence, formation, prevention, removal and oral health effects of supragingival and subgingival deposits. Eur J Oral Sci. 1997;105:508-22.  Back to cited text no. 7
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Blake M, Bibby K. Retention and stability: A review of the literature. Am J Orthod Dentofacial Orthop.1998;114:299-306.  Back to cited text no. 9
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Katsaros C, Livas C, Renkema AM. Unexpected complications of bonded mandibular lingual retainers. Am J Orthod Dentofacial Orthop. 2007;132:838-41.  Back to cited text no. 18
Hichens L, Rowland H, Williams A, Hollinghurst A, Ewings P, Clark S, et al. Cost-effectiveness and patient satisfaction: Hawley and vacuum-formed retainers. Eur J Orthod. 2007;29:372-8.  Back to cited text no. 19
Zachrisson BU. Long-term experience with direct-bonded retainers: Update and clinical advice. J ClinOrthod. 2007;41:728-37; quiz 749.  Back to cited text no. 20
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Pratt MC, Kluemper GT, Hartsfield JK, Jr, Fardo D, Nash DA. Evaluation of retention protocols among members of the American association of orthodontists in the united states. Am J Orthod Dentofacial Orthop. 2011;140:520-6.  Back to cited text no. 23
Renkema AM, Renkema A, Bronkhorst E, Katsaros C. Long-term effectiveness of canine-to-canine bonded flexible spiral wire lingual retainers. Am J Orthod Dentofacial Orthop2011;139:614-21.  Back to cited text no. 24
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  [Figure 1], [Figure 2]

  [Table 1], [Table 2], [Table 3]


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